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  • [Michael] Where is everyone?

  • We have been listening for messages from outer space

  • for more than half a century,

  • and so far...

  • silence.

  • Why?

  • Are we truly alone in the universe?

  • Or is everyone else acting like us

  • and just doing a lot of listening?

  • Maybe we need to be louder.

  • Maybe we need to send more messages out there.

  • But how do you write a letter to an extraterrestrial

  • whose language and culture and biology and mind

  • we have no concept of?

  • And what do you say?

  • And given all of the unknowns about what they might be,

  • should we say anything at all?

  • ♪♪

  • Ever since I was a kid,

  • I've wanted to design a message

  • that is sent to outer space.

  • A sort of hello from Earth to whatever extraterrestrials

  • might be out there.

  • I mean, come on, to be the author of the first thing

  • aliens ever heard from our entire planet

  • would be a fantastic honor.

  • And as it turns out,

  • an opportunity to send a message to space

  • has been given to me.

  • But it might be a waste of time.

  • What if there isn't anything or anyone out there to receive it?

  • The fact that we still have no evidence

  • of intelligent alien life

  • despite the high probability that such life exists,

  • is called the Fermi paradox.

  • And there are many entertaining theories

  • that attempt to explain it.

  • One explanation is the theory

  • that whenever two civilizations meet,

  • destruction always results.

  • Which is why in 2015,

  • several prominent experts wrote a letter

  • warning against making any contact at all.

  • [Stephen Hawking]

  • Ideas like that suggest that perhaps we should remain silent,

  • send no messages to space.

  • But Doug Vakoch disagrees.

  • He is the president of METI,

  • an organization that, despite all of these concerns,

  • is nonetheless actively messaging

  • extraterrestrial intelligence.

  • If I want to design a message for life out there,

  • I should talk to him first.

  • Why isn't he afraid?

  • I met up with Doug

  • at the Chabot Observatory,

  • home to the largest public refractor telescope

  • in the Western United States.

  • -[Douglas] So here we are. -[Michael] Wow.

  • [Douglas] Yeah.

  • This was one of the prime telescopes of a century ago.

  • This is really an antique.

  • [Michael] Jeez! I've seen so many observatories

  • and so many big telescopes in pictures.

  • Believe it or not, I've never been this close to one.

  • [Douglas] This is a huge instrument,

  • and yet it's balanced too exquisitely.

  • I'm like a super person. Oh!

  • [Douglas laughs]

  • It had quite a bit of momentum there.

  • I'm scared to look.

  • I'm telling you, I had no idea I would have this feeling,

  • -seeing a telescope this big. -[Douglas] Well, it is, it is.

  • Can I handle what I would see?

  • I think you can. I think you can.

  • You just take a look.

  • Ah-ha.

  • -Absolutely nothing. -[Douglas] Not tonight.

  • -Because of the fog. -Because of the fog.

  • [Michael] Just the fog coming in is pretty darn cool.

  • The universe has existed

  • longer than we have,

  • but we've only been actively listening for life out there

  • for the last half century.

  • In 1960, astronomer Frank Drake began the search

  • with a 85-foot radio telescope.

  • He scanned for interstellar radio waves,

  • but did not detect any recognizable signals.

  • Soon after, SETI, or Search for Extraterrestrial Intelligence,

  • was formed to continue our search

  • for other life in the universe.

  • [Mission Control] Liftoff.

  • [Michael] Besides just listening,

  • we've also launched physical messages

  • like the Golden Records we put aboard

  • both Voyager spacecraft in 1977.

  • The records were recordings of images and sounds from Earth

  • that told a story of who we are as Earthlings,

  • as well as coded instructions on how to play them back.

  • Today, Doug and his team at METI

  • are on a mission to send new messages to the stars.

  • Thank you for taking some time to have a conversation with me.

  • My first question is simply this:

  • where is everyone?

  • Are we alone?

  • I don't think so.

  • You know, we've been looking

  • for over 60 years.

  • And so that leads some people to say we must be alone.

  • The reality is, though,

  • we have just begun the search.

  • I mean, we've looked at a few tens of thousands of stars,

  • and there are 400 billion stars in our galaxy alone.

  • Billions of galaxies in the universe.

  • So I think we just need to keep on looking.

  • When you put it that way,

  • it actually isn't that surprising, is it?

  • I mean, we are still discovering species on our own planet today.

  • At METI, we switch the process,

  • and instead of just listening for signals,

  • we send powerful, intentional signals to other stars

  • in the hope of getting a reply.

  • What do you say to people who go, "Hold on,

  • "we should not be alerting any life out there to our presence.

  • "It's just not worth the risk.

  • In fact, it's irresponsible."

  • I would say it is too late.

  • The horse is out of the barn.

  • We have been announcing our presence to the universe

  • since the beginning of radio and television.

  • Any civilization that has the ability

  • to travel between the stars

  • already picked up I Love Lucy.

  • So maybe the aliens have been observing us,

  • but they're waiting for us to break the silence.

  • So our goal isn't to let them know

  • we're here for the first time.

  • It's to really give an indication

  • that we want to make contact.

  • The one thing that's keeping me from being really excited

  • and comfortable about sending a message out

  • is that a lot of prominent people have said, "Don't."

  • There are some group of scientists who have said

  • you shouldn't be doing this.

  • Stephen Hawking.

  • But that's an example of someone very prominent

  • who said you shouldn't transmit,

  • because maybe the aliens will come to Earth.

  • To me it's notable that, after his death,

  • to commemorate his life, his family,

  • they transmitted his voice out into space.

  • Anyone and everyone can transmit to extraterrestrials.

  • So I think it's an incredible contradiction

  • for people involved in SETI to say we shouldn't transmit,

  • because the day they succeed, everyone will be transmitting.

  • Okay, so how do we craft a message for E.T.?

  • Well, it depends what we would want to do.

  • I would want to know something about that civilization.

  • And so then we try to figure out,

  • what is it that we have in common

  • with the extraterrestrials?

  • What do you think the aliens would know that we know?

  • I always go to math.

  • So that's the natural starting place.

  • But how can you communicate the idea of numbers?

  • Like this.

  • [both clap]

  • -Hey, look, we're communicating. -Okay, okay, great, great.

  • You could keep that up. You could use that

  • to count up to a million.

  • But that doesn't capture what it is to be human.

  • Right.

  • So you want to tell a little bit about yourself.

  • The goal, for me, is to learn about other civilizations

  • if, in fact, they're out there.

  • But I think even if they're not,

  • simply this process of reflecting on what stories

  • do we want to tell about ourselves,

  • how do we want to represent ourselves to the universe,

  • forces us to look at ourselves anew.

  • And I think that can only be good.

  • One of my favorite messages

  • that humans have ever sent for extraterrestrials

  • to some day receive was written in 1974

  • by Frank Drake and Carl Sagan.

  • They sent the message to a star cluster 25,000 light years away.

  • It contained 1,679 binary digits

  • that, when decoded,

  • created an image:

  • the famous Arecibo message.

  • This message is full of general information about us.

  • Up here in the white are numbers.

  • Now, since math is probably pretty universal,

  • I feel like it's fair to say

  • that aliens will understand that part.

  • But what about some of these other parts?

  • This is a human figure, but will aliens be able to tell

  • that that is supposed to be

  • the shape of the thing that made this?

  • Could an alien figure out what all these symbols mean?

  • For that matter, could a human even correctly figure out

  • what they all mean?

  • And I bet that if you were to ask two people

  • to guess what all this means,

  • you would get two different answers.

  • I want to give some humans a message,

  • and I want to see how quickly they come up with meanings

  • I didn't put in there, or conflicting interpretations,

  • because if that happens,

  • well it could spell trouble for our ability to say much more

  • than simple mathematical truths to whatever might be out there.

  • To help me answer this question,

  • I recruited Dr. Steve Vance.

  • Dr. Vance leads a habitability team

  • for JPL's Astrobiology group,

  • meaning it's his job to think about the possibility

  • of life on other planets.

  • I don't think it's crazy

  • that if the Arecibo message is received,

  • the alien civilization that gets it

  • will see all kinds of meanings in it.

  • They're going to see things through the lens

  • of how they experience their world.

  • And I think if we received a message from outer space,

  • we would think of the ones we've sent out,

  • and we would look for these pieces in it.

  • And maybe the message contains none of those things.

  • I'm really curious about this hypothesis

  • that they will find meaning where there isn't any.

  • There's only one way to find out.

  • -Yeah. Let's do it. -Let's do it.

  • [Michael] To find out how individuals' own backgrounds

  • would influence their approach to a message from space,

  • we sought out a veritable A-team

  • of critical thinkers and problem solvers

  • to put to the test.

  • I'm a sophomore engineer, and I have a PhD in physics.

  • I'm a game designer and programmer.

  • I am a professional poker player.

  • I'm a graphic artist and app coder.

  • I teach college courses in writing film and psychology.

  • This set of experts would be told

  • that the message they were receiving

  • was intercepted from outer space,

  • and would be asked to decode it

  • using a variety of office supplies

  • and computer software.

  • What they didn't know is that

  • although similar to the original Arecibo message,

  • our message is just noise.

  • Would our group of experts notice

  • that there was nothing to get,

  • or apply their own meanings to this indecipherable message?

  • It was time to find out.

  • We received a message

  • using a radio telescope from outer space.

  • Not the kind of thing that naturally happens.

  • What we want to know is what it says.

  • A copy of the message as received is on that laptop.

  • This is an audio output of that message.

  • Using your individual expertise

  • and the tools that you have in front of you,

  • please figure out what this message is saying.

  • This is not an easy task.

  • -Okay. -Good luck.

  • -Okay, you ready to listen? -Let's hear it.

  • Here we go.

  • [pings]

  • Before the team can interpret

  • that our jumbled image is meaningless,

  • they first have to figure out that they're supposed

  • to decipher it visually.

  • This would be the first step for any alien civilization

  • who received the real Arecibo message.

  • To do that, the first step is to recognize

  • that it's binary.

  • There are two different tones in the message.

  • [man] Is there a difference in time between any of these?

  • [woman] It doesn't look like it. The rhythm doesn't vary.

  • [man] It doesn't vary?

  • There's going to be a repeating pattern in there, probably.

  • It seems like there's only two notes.

  • Yeah, it doesn't seem to go any higher or lower than that.

  • So there's only two tones. We're thinking some kind

  • of binary message, zeros and ones,

  • We should probably start transcribing it

  • and look for repeating patterns.

  • Right off the bat, all right?

  • They're noticing two tones, binary message.

  • I think that's a very human thing to do,

  • because we already come to this

  • knowing that binary is this great way to talk, right?

  • So we're already seeing into it what we expect to see.

  • Okay, so, we have a way to encode binary into letters.

  • So if an alien intelligence is sending things,

  • we obviously wouldn't know that,

  • -and it wouldn't be the same language anyway. -Right.

  • So they're probably just sending us straight numbers.

  • Like, there's, you know, universal language and all that.

  • So we got to find out what those numbers are.

  • Okay, let's have three people do this,

  • just so we make sure we don't miss anything.

  • Let's do zero for low, one for high,

  • and let's start writing it down.

  • [woman] Zero, one, zero, zero, zero...

  • Now they are creating a visual representation

  • of these different tones.

  • The key is to see how many tones there are.

  • -Zero, zero-- -Oh, wait, sorry. I got it.

  • [pinging]

  • [woman] Do we need to play it in half time

  • -because I feel like we're scrambling. -Yeah, we're just scrambling.

  • [man] No worries, no worries.

  • [Michael] The message is 17 minutes long,

  • with 1,679 individual tones.

  • Because this would take so long to transcribe,

  • I decided to help them speed up the process.

  • This thumb drive contains a transcription of the message,

  • pretty much just like what you're doing right now.

  • -But now you're just kind of jumped ahead in time. - Fast forward, yeah.

  • -Here it is. -Thank you.

  • -All right, we will continue. -All right, I'll leave you guys to it.

  • [man] Okay, this is pretty long here.

  • [woman] It's not repeating at all.

  • Does it look like an even distribution

  • of zeros and ones?

  • No, there's way more zeros than ones.

  • -[woman] Yeah. -[man] Okay.

  • So, what is the total number of--?

  • [woman] 1,679 total.

  • [man] 1,679. Is that divisible by anything in particular?

  • -It's a prime number. -Could be a prime number.

  • It's going to be hard to test that without writing a script.

  • Just divide, divide, divide, divide.

  • [man] Let's do a little division.

  • [Michael] Just like the Arecibo message,

  • our meaningless image contains

  • 1,679 total tones.

  • The number 1,679 can only be divided into two prime numbers:

  • 23 and 73.

  • When you arrange the ones and zeros

  • from the message into a 23-by-73 grid,

  • the jumbled image will begin to emerge.

  • If the group can discover this feature of 1,679,

  • they may be able to start breaking down the tones

  • of the message into an image.

  • Ooh. Ooh!

  • Hey, it's-- hey, yo, this is important, guys.

  • This number breaks down to 23x73.

  • Okay.

  • Ah-ha. There it is.

  • And that is the only breakdown,

  • because 23 and 73 are prime numbers.

  • So that's its prime factorization.

  • So that is very relevant.

  • Wow. Look at the big brain on that dude.

  • [man] Do you think it's worth it

  • to try and straight up, like, make a 23-by-73 grid,

  • and then you could say that the lows are white

  • and the ones are black,

  • and maybe there's some kind of image being sent there.

  • I like that idea.

  • Hey.

  • [man] I'm strongly with the graph idea.

  • [woman] What I'm doing right now is I'm pasting it into Excel,

  • -and then we can graph it in Excel and see. -Yeah, that's good.

  • [Bonnie] You mean like fill the cells

  • -Yeah. -and make the numbers white, and all that?

  • Yeah.

  • She's going to try to make this a little easier by coloring

  • -all of the cells that have a one in them. -That's great.

  • We picked these people because of their knowledge

  • of mathematics and physics and music.

  • But their knowledge of how to use Excel

  • is proving to be the best skill.

  • Amazingly, in just a couple of hours,

  • the team figured out how to break down

  • our fake Arecibo message into an image.

  • Will they try to find meaning in the message,

  • or will they realize it's just noise?

  • Oh, I'm done! Guys, I'm done!

  • -Oh, you did it. -That was fast.

  • [man] That looks sadly random.

  • That almost looks like it's going to resolve into something.

  • [woman] Maybe it's a map.

  • -Those aren't letters, are they? -They could be.

  • [man] No, they're all back half of the alphabet, then.

  • Except for little nine over here.

  • Little nine. Look at that little nine.

  • -[woman] Baby nine. -[man] That's an "I", right?

  • I'm pretty sure there's nothing there.

  • There's no pattern here.

  • Do we agree, like, this probably looks like nothing?

  • [woman] Yeah, I don't think going any further with this is really...

  • -Productive. -Okay.

  • Our group had followed the clues correctly

  • and built out an image,

  • even though there wasn't one that made sense.

  • And, incredibly, they didn't try to make sense of it.

  • Within a matter of minutes,

  • they realized it was random and moved on.

  • So it was time to let them in on the ruse.

  • Hello, again.

  • All right, so, this is Steve Vance.

  • He's taken the day off from JPL.

  • Have you learned anything about the message?

  • What do you know?

  • It seems very random still.

  • Though it did have a nice prime factorization.

  • That did not seem random to me.

  • Let me show you guys something new.

  • [man] What the heck?

  • It looks like 23 across.

  • -I see how you're doing this. -Oh, we were almost there!

  • We tried arranging these ones and zeros

  • kind of in these blocks.

  • [woman] But there's some patterns repeating there

  • that we don't actually have mapped correctly here.

  • [Michael] Now, this is not the message that you're looking at.

  • This is the famous Arecibo message.

  • Now, what you have been working on

  • is this message,

  • but randomized.

  • [laughs]

  • Thanks a lot.

  • [all laugh]

  • Oh, I'm just going to collapse on the ground now.

  • In a way, you guys were quite successful.

  • You, first of all,

  • recognized the semi-prime nature of this message very quickly,

  • and tried to build an image.

  • I was wondering if you would start

  • to see things there that weren't.

  • But it didn't really happen, did it?

  • I think the real reason that we weren't interpreting

  • anything out of that

  • is we were looking for clearly defined patterns.

  • We're looking for something like this.

  • This is actually what we're looking for.

  • Even symmetry would have been a big thing for me.

  • If I'd seen any symmetry in these patterns,

  • I would have said, "This is not random."

  • I'm also interested in knowing

  • the best kind of message to send,

  • because I have an opportunity to send a message.

  • You know, a marker to where we are

  • is kind of the biggest thing for me,

  • but then it's like, do we really want to tell them where we are?

  • Is that something-- Do we want them to come visit?

  • -I don't know. -What do you guys think?

  • Should we be sending messages to outer space?

  • [all] Yeah, yes.

  • [Matthew] I don't think we should.

  • Every single time any civilization

  • encounters any other civilization,

  • and one is technologically advanced, one guy gets crushed.

  • You know, what if they're not more advanced than us?

  • What if we're at the same place,

  • and the only way we can communicate is like this?

  • What if we can just exchange the recipe for fusion?

  • We would have so much to learn from those people,

  • and really nothing to lose in that situation.

  • You're making an argument

  • that we almost have a moral imperative

  • to send our knowledge to share with other civilizations.

  • -Absolutely, yes. -It's a really interesting point.

  • That's kind of where I land.

  • Let's just think of this as a way

  • to preserve the stories that we've been able to tell,

  • which, by the way, we tell better than the universe does.

  • Thank you all so much. This was a phenomenal exercise.

  • [all] Thanks. Thank you.

  • You know, honestly, I thought that the human tendency

  • to find meaning where there is none would more quickly emerge.

  • But that didn't really happen.

  • What I also didn't expect was just how educational

  • the whole challenge would be.

  • I mean, I saw some human flaws and biases at work,

  • but more generally, I saw the human mind at work,

  • who we are.

  • Which kind of makes sense, right?

  • I mean, the Voyager Golden Record

  • really isn't just a neat thing for extraterrestrials.

  • It's a neat archive by, of and for us.

  • I don't think we will all ever agree

  • about whether or not we should be sending messages

  • to outer space announcing that we are here.

  • But here's the thing.

  • Sending focused messages to outer space

  • requires technology that not all of us have.

  • So only those with access

  • can say hello to extraterrestrials if they want.

  • But who chose them to speak for us,

  • for all of Earth?

  • Well, I've come here, to Vazquez Rocks State Park,

  • to talk to a man who is changing that.

  • He is democratizing active SETI, because the service he has built

  • is allowing anyone to send any message they want

  • to outer space.

  • He's an expert in the field of alien communication

  • with a doctorate in elementary particle physics,

  • and he's the one who's going to help me send my message.

  • Tell me about the way you are talking to aliens

  • and helping other people do it.

  • Well, I have built a website, called SpaceSpeak.com.

  • And it allows people to send a text in audio

  • or a image message out into space.

  • My view is, as many people that can reach out to aliens

  • or the universe in general, the better.

  • What are you using to transmit these messages?

  • Radio waves. Radio waves are just another form of photon.

  • And once a photon is broadcast into space, it persists.

  • It never dies. It never decays.

  • A million years from now, maybe the earth is gone,

  • maybe the solar system is gone,

  • but your message is still out there,

  • and essentially become archaeological photons

  • for some future generation to see what we were about.

  • -I want to do this. -Absolutely, let's do it.

  • -Awesome. -Great.

  • Going to take a chair right here.

  • -And... -This is it.

  • This is the Space Speak transmitter.

  • This is a transmitter box here.

  • And the antenna is right back here.

  • I've been thinking about this a lot,

  • and I've spoken to a lot of people

  • about what to send, how to write the message,

  • and whether or not I should send anything at all.

  • I don't think this is something to take as fact.

  • It's my personal opinion.

  • I don't have any fear that this is dangerous.

  • -Yeah. -I spent a lot of time

  • constructing what I believe

  • to be a really neat, clever idea.

  • I was going to not send a two-dimensional image

  • like the Arecibo,

  • but a three-dimensional image made of voxels.

  • And I got really into this.

  • And then after talking to you and really thinking about

  • the point of communicating with outer space,

  • beyond Earth,

  • I...I just think

  • to decide what to say and how to say it.

  • is an exercise in learning how we communicate at all.

  • -Yes. -It's always coming back

  • to who we are.

  • My grandmother passed away a few days ago.

  • I'm so sorry to hear that.

  • I'm actually leaving tomorrow to her funeral,

  • and I'll get to see all of my family.

  • And obviously I'm never going to forget my grandma.

  • And the way she, you know, made me who I am,

  • that will, in a way, like echo like ripples in a pond, right?

  • For generations to come.

  • But this is a message made of light

  • that will be around forever...

  • until the universe ends, somehow.

  • So I have the last photograph

  • that was ever taken of us together.

  • I'd like to send that picture out.

  • -Let's do it. -Okay.

  • This photo is her in the hospital,

  • using one of those, like, grabber tools, you know,

  • to pull my beard hairs and hurt me.

  • [laughs]

  • And she was so weak, but with that tool,

  • she could pinch.

  • -Oh, that's awesome. -It's a great picture

  • of who we were.

  • She wasn't a big fan of aliens

  • as far as I know,

  • but it's us caught in this moment

  • that I think I want to remember,

  • and I want the universe to remember.

  • So...

  • well, let's do it.

  • Yeah. Go ahead and hit "send."

  • Wow. It's sent. And look at that.

  • -It's already 229,435 miles away from Earth. -Yes.

  • I don't think she ever traveled that far in her entire life.

  • -Now she has. -She has now, absolutely.

  • [Michael] And she will continue traveling.

  • Your grandmother will touch the universe. Yeah.

  • Peter, thank you very much.

  • You are very welcome, sir. It was a pleasure.

  • [Michael] And, as always,

  • thanks for watching.

  • ♪♪

[Michael] Where is everyone?

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A2 初級

如何與外星人交談 (How to Talk to Aliens)

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    林宜悉 發佈於 2021 年 01 月 14 日
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